Toxicological evaluation of entomotoxic silica nanoparticle

Abstract

Pest management researchers currently reappraise the use of inert dust-based insecticides because of the growing problem of environmental pollution and increasing insect resistance associated with conventional insecticides. Diatomaceous earth, which is amorphous micron-sized silica derived from fossilized phytoplankton, has become popular as an alternative insecticidal agent in European countries. In this investigation the insecticidal efficacy of amorphous lipophilic silica nanoparticle was examined on red flour beetle (Tribolium castaneum), a stored grain insect pest. The biosafety of this silica nanoparticle formulation was studied in MRC-5 cell line with water-soluble tetrazolium and lactate dehydrogenase activity assays. Acute oral toxicity of these nanocides was studied in mice model following OECD guidelines for testing of chemicals as well as the effects of particle exposure on mouse blood parameters, serum biochemical levels, and histopathological changes in various organs.

Keywords:

• silica nanoparticle
• entomotoxicity
• biotoxicity

Acknowledgments

Authors would like to thank Department of Biotechnology, Govt. of India, (DBT) (Grant Nos BT/PR9050/NNT/28/21/2007 & BT/PR8931/NNT/28/07/2007) and NAIP, ICAR (Grant No. NAIP/Comp-4/C3004/2008-09) for their generous financial support. ISI plan project for 2008–2011 was also used for funding this work and collaborative efforts. Authors are also thankful to Ms Indrani Roy for her valuable suggestions regarding this manuscript.